In this paper, we propose an efficient methodology for detecting magnetic field and thereby magnetic patterns using an injection-locked spin-torque nano-oscillator (STNO) array. We demonstrate the methodology with the implementation of a physical STNO model based on the Landau–Lifshitz–Gilbert–Slonczewski equation, which is benchmarked with experimental data. Based on our simulations, we provide an analysis of how the STNO, as a field-controlled oscillator, together with injection locking, can be used to sense magnetic fields and thereby magnetic patterns. The output can be sensed using simple CMOS peripheral circuitry.